A hypothesis that can be supported with large numbers of observations and experiments is known as a theory. To put it another way, a theory is a deep-rooted hypothesis. However, although a theory is proven with experiments, it may also be disproved.
For example, the claim that "The atom is the smallest known component of matter," known as Dalton's atomic theory, today has lost all validity.240 Advances in science and technology have revealed the existence of much smaller particles than the atom and even the proton, such as the quark.

A scientific theory is an attempt to explain certain phenomena occurring in nature. A frequently occurring phenomenon may be explained in terms of a theory, a fact, or a law. Gravity, example, is a fact. Even if we cannot perceive gravity directly, we can still see its effect when we drop something. There is also a theory of gravity that answers the question of how this takes place. Even if we do not know exactly how gravity works, there are theories that seek to account for it. The law of gravity formulated by Isaac Newton is one such.

In summary, a scientific fact is an observable natural law, and a scientific theory is a mathematical description of how a scientific law works.

The first and most important requirement of empirical (experimental) science is that the object or phenomenon we wish to investigate should be observable. The second condition is that the object or phenomenon should be repeatable. Any observable and repeatable event must be capable of being tested. This enables us to determine whether or not an experiment validates a theory. If the explanation that someone postulates regarding a phenomenon is one that cannot be tested or validated, then this is not a theory, but a belief.241

Evolutionists say that the main evolutionary changes take place very slowly, or so rarely that people cannot observe them during their lifetimes. According to the evolutionist Theodosius Dobzhansky, even when evolutionary changes occur, they are events that by nature are rare, unrepeated and irreversible. Paul Ehrlich, a well-know evolutionist, maintains that the theory of evolution cannot be refuted by any observation, for which reason it needs to be regarded as being outside the scope of empirical science.242

On the other hand, by suggesting that evolution takes place in two ways-observable micro-evolution and unobservable macro-evolution-evolutionists attempt to portray this imaginary evolutionary process as a scientific fact. (SeeThe Invalidity of Micro-Evolution and The Macro-Evolution Myth.) According to evolutionists, macro-evolution is the process of infinite variation necessary for reptiles to turn into birds, or apes into human beings. Yet nobody has ever observed this happening.243

Micro-evolution, on the other hand, again according to evolutionists, is a limited process of variation of a specific species that we can observe and that produces divergence. However, the changes postulated as micro-evolution cannot produce a new species or a new characteristic. Therefore, they are not, as is claimed, mechanisms with any evolutionary power. In addition, micro-evolution is raised in order to imply that it is a dorm of variation that gives rise to macro-evolution. (SeeVariation.) This is mere conjecture regarding a phenomenon that cannot be observed and which lacks any evidence.

Evolution cannot be observed and cannot be repeated, and for these reasons, is therefore not a scientific fact or theory. Neither is it an evident scientific fact, as some circles imagine or as they seek to portray it.244 On the contrary, when the theory of evolution is compared with scientific findings, a great contradiction emerges. In terms of the origin of life, population genetics, comparative anatomy, paleontology and biochemical systems, the theory of evolution is in a state of crisis, as the famous biochemist Michael Denton puts it.245